the trunk. The very rare L. midas has been found in old pigeon nests or squirrel dreys.
Tree trunks provide another habitat used by some species of spider. The bark of the older trunks
provides the best variety of cracks with its deep fissures and lichen flora. Silk retreats are made in the
fissures or under the bark and there is spacial variety available for the webs of different species. The
cribellate spider Amaurobius fenestralis is very common. It has a specialised plate just in front of the
spinners (Fig. 2-4), called the cribellum, for producing very fine threads of silk which are combed out
with the calamistrum, a comb present on the fourthpair of legs. The tangle of silk which is produced
has a characteristic bluish tinge and can often be seen on tree trunks. The spider itself is much more
difficult to find unless it can be enticed out from hiding.
The six-eyed Dysderid spider Segestria senoculata is almost tubular in shape. It makes a silk tube
in crevices in the bark and up to a dozen stout threads radiate outwards from this to act as lines to
sense the prey. It is possible to persuade the spider to appear by tickling one of the threads with a blade
of grass or a tuning fork.
The recorded occurrence in the Forest of the crab spider Philodromus margaritatus and jumping
spider Marpissa muscosa has already been mentioned. Both species occur on the bark of trunks where
their colours provide them with excellent camouflage. It is to be hoped that both these species will be
rediscovered.
Salticus cingulatus is another jumping spider that occurs on tree trunks. The species was recorded
by Frank P. Smith from Edmonton Marshes but this is outside the area now considered to be Epping
Forest. Although not uncommon in some parts of England the species has never been recorded in
Essex. The zebra spider Salticus scenicus is often seen on the walls of houses and sheds but it has also
been found on tree trunks in the Forest. Like other jumping spiders the species has very good eyesight
and stalks prey rather like a cat. When it gets close enough the spider will finally jump, capturing the
prey and transfixing it with its fangs. A drag line of silk is always used so that if the spider misjudges
the leap it will not fall to the ground but will be able to climb back again. Jumping spiders have the
most endearing quality of peering into the lens of the natural history photographer while he or she
struggles to get a high quality slide that is still in focus!
Achaearanea lunata is a handsome Theridiid spider with a pretty pattern and high abdomen. It
makes its scaffolding web attached to the side of tree trunks with a tent like retreat made from pieces
of fallen leaf. If disturbed the spider will drop directly down towards the ground, with a drag line to
enable it to climb back up again later. Although thought to be a rare spider it seems to be reasonably
widespread in Essex.
The Araneid Nuctenea umbratica is a spider of tree trunks but also fences and the eaves of houses.
It makes the characteristic Araneid orb web usually suspended between the trunk and a small side
twig or branch. The spider itself is likely to be hidden under the bark where its flattened abdomen
helps it to move into the available crevices. The spider usually becomes more active at dusk when it
may make an appearance, waiting for prey to be caught in its web.
Several Linyphiid spiders are characteristic of the tree trunk habitat. The small dark species
Moebelia penicillata and Meioneta innotabilis can sometimes be found running about on the surface
of the bark in large numbers in early summer. The larger and lighter patterned Drapetisca socialis can
be found mature in the autumn.
Grasslands
The ant-like Gnaphosid spider Micaria pulicaria is probably common in grassland areas. It has a
very dark brown or black colour with white markings and the abdomen has a beautiful iridescence.
The spider runs about in very fast dashes with its front legs quivering like the antennae of an ant and
this seems to protect it from its enemies.
The grassland plains are home to ground living species like the crab spiders Xysticus cristatus and
X. erraticus. The X. cristatus male takes the extraordinary precaution of tying the female down with
silk strands before mating with her, an action that I was once lucky enough to witness and photograph
in early summer.
The Salticid Euophrys frontalis is a jumping spider that often occurs in grassland. The colourful
male has a very different appearance to the rather drab female. It has orange hairs on its face around
the four large front eyes and the palps are clothed in white hairs. Unlike most other spiders Salticids
have excellent eyesight and the male uses his palps to signal to the female to court her and make sure
that she does not regard him as prey.
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